Improvement: Use anticipate class declaration instead of include header

git-svn-id: svn+ssh://svn.tuxfamily.org/svnroot/qet/qet/trunk@3224 bfdf4180-ca20-0410-9c96-a3a8aa849046

sources/qetgraphicsitem/elementtextitem.h

@@ -17,10 +17,12 @@
 */
 #ifndef ELEMENT_TEXT_ITEM_H
 #define ELEMENT_TEXT_ITEM_H
+
 #include "diagramtextitem.h"
-#include <QtXml>
+
 class Diagram;
 class Element;
+
 /**
 	This class represents a text item attached to an element. Users can change its
 	value, adjust its position (defined relatively to its parent element), and